There are a lot of very interesting stats, but "wins produced" is the most telling IMO.
Everyone associates stats with baseball, but statisticians have shown stats are just as powerful, probably moreso, in hoops. The outcome of a basketball game is unlike baseball and football because outcomes are the results of simple math. Who best executed on these 3 factors: scoring efficiency, rebounding, and turnover margin?
If you do all 3 better than the opposition you will always win. If you do all 3 worse, you will always lose. If you don't rebound well, you better make up for it by smashing the other 2 categories. Etc. Every win or loss is explained by the combination of these factors.
Wins produced is a stat created by regression modeling based on this principle, but expanded to evaluate individual contributions.
WP = shots made + rebounds + assists + steals + blocks - fouls - turnovers - shots missed
These factors have a very strong relationship with winning, and it turns out being a good basketball player has nothing to do with scoring 25 ppg, and has everything to do with making more positive plays, than negative plays.
Here is a much more complicated explanation:
How to calculate Wins Produced
Here is a site where you can get player rankings in terms of wins produced:
The NBA Geek - Advanced NBA Statistics for all players